Various structures have been invented and used for many different purposes. In particular applications, flexure of structures has been taken into consideration and designs have been invented or selected to allow a structure to flex as needed in the particular application at hand. Needs and potential for benefit exist, however, for new and improved structures that provide a beneficial measure of stiffness while providing better flexibility, at least in certain dimensions. In addition, many different shapes and sizes of springs have been used for many different purposes. Needs and potential for benefit exist, however, for springs having new shapes that may fit better into particular available spaces, that may have different force-displacement characteristics, and that may have other unique characteristics that may prove to be advantageous in certain applications. Thus, the potential for advancement in the areas of flexible structures and springs have not been exhausted. Needs and potential for benefit also exist for flexible structures and springs that are inexpensive or easy to manufacture, easy to use, are reliable, and provide the benefits desired in particular applications.
In a particular area of technology, bandages have been used to protect wounds. Wounds or damage to the skin or other tissue occur quite frequently and most people experience various different wounds during their lives. Wounds, as the term is used herein, may occur accidentally or may be the result of a surgery, as examples. While many wounds may heal relatively easily, many types of wounds such as scrapes, burns, skin grafts, etc., as examples, are sensitive to subsequent damage. In order to heal, many wounds need protection from foreign matter such as dirt or bacteria, but may also benefit from protection from physical contact. Disturbing such a wound may cause pain, increase healing time, cause additional scarring or damage, worsen the patient's health, or a combination thereof, as examples. In may instances it is desirable to protect a wound from further damage in the area of the wound.
Bandages have been used to protect wounds from foreign material, and, to some extent, from impacts, but bandages typically have not been very effective at protecting wounds from forces perpendicular to the skin or tissue. Casts have been used to immobilize limbs when bones have been broken, for example, and casts are resistant to generally perpendicular forces, but casts generally do not allow the limbs or tissue to move. In addition, it is often desirable to keep the bandage or wound covering from touching the wound. Often, the covering will stick to the wound if it touches the wound, causing damage to the wound if the covering is removed or even when the wound moves as the person moves their body. In some applications, it is desirable that a wound covering allow for unrestricted or less-restricted motion of the wound. Wounds frequently occur on joints or areas of the body where the skin moves, stretches, or shifts significantly when the person makes ordinary movements such as walking, eating, etc. Treating wounds on joints is thus difficult because joints require complex motion. In order to allow movement of a joint, a wound covering placed on the joint must often allow simultaneous bending, stretching, and twisting, as examples.
Wounds are often treated by placing ointment or medication on the wound and then placing a bandage on the wound. The bandage typically contacts the wound. Having the bandage contact the wound is often undesirable as the bandage may stick to the wound, causing damage to the wound when the bandage is removed or when the wound moves due to the person moving. Additionally, a bandage which contacts the wound may cause pain or further damage to a sensitive wound such as a burn, or may irritate the wound, possibly causing increased inflammation or causing the person to scratch at the wound, as examples. Conventional bandages do little to prevent accidental contact with the bandage from pressing against the wound. Thus, a bandage which contacts the wound may cause further damage or an increased level of discomfort.
Various attempts have been made to provide a wound covering which is elevated above a wound so that the covering does not touch the wound. For example, a covering has been designed which uses a foam square around the perimeter of the wound covering with a sheet of covering material attached thereto. The foam square keeps the covering material elevated off of the wound. The foam bends fairly easily in one direction perpendicular to the wound covering, but thereafter may not be able to bend in another direction to form a compound curve. The wound covering also may not be able to easily stretch or change shape within the plane of the wound covering because the sheet of covering material essentially forms a shear web.
Another wound covering uses a domed plastic cover with a corrugated section formed across the center thereof to provide flexibility. This type of design, however, has several limitations. Larger corrugations provide increased flexibility but increase the bulkiness of the wound covering, either increasing the overall height of the covering or reducing the distance between the covering and the wound. Smaller corrugations are less flexible. A stronger material of construction increases the resistance of the wound covering to collapse, but reduces the flexibility. Softer materials provide improved flexibility, but reduce the strength of the covering and allow it to more easily collapse against the wound. These corrugated wound coverings provide some flexibility for bending at the corrugated joint in a lateral or vertical direction, but allow for little twisting, stretching, or skewing of the shape. Thus, they do not provide adequate flexibility for use on many locations of the body.
Therefore, there is need for or potential for benefit from a strong, flexible, low profile wound covering. There is also a need for or potential for benefit from a wound covering which prevents contact with the wound. Further, there is also a need for or potential for benefit from a wound covering which is sufficiently strong to prevent collapse thereof, but which is capable of easily bending, stretching, twisting, and skewing so as to accommodate the similar movements of the skin when a person moves.
There are also needs for and potential for benefit from other structures which are flexible. Specifically, there are also needs for and potential for benefit from other structures that are stiff when loads are applied in one direction and yet are flexible in other directions, for example, when supports or a supporting surface for the structure moves relative to other supports or portions of the supporting surface. Such flexible structures may be used as springs, for example. Other needs and potential for benefit may be apparent to a person of skill in the art of structural design.